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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
491

Feedback Control in Treatment for Apraxia of Speech

Potkovac, Grace, 0000-0003-0475-4064 January 2020 (has links)
Apraxia of speech (AOS) is a motor speech disorder associated with an impairment in motor planning and programming. It is therefore a logical step to derive treatment of the disorder from the principles of motor learning. Principles of motor learning refer to relatively predictable benefits of certain practice conditions over others (e.g., random practice enhances learning compared to blocked practice). A number of studies have begun to examine principles of motor learning in treatment for AOS (e.g., Austermann Hula et al., 2008; Katz et al., 2010). The current project aims to continue the investigation of motor learning principles and its application to motor speech disorders. In particular, the primary goal of this study is to examine the role of feedback control in treatment for AOS. Two types of feedback control are typically distinguished: self-controlled feedback and clinician-controlled feedback (Chiviacowsky & Wulf, 2004; Chiviacowsky & Wulf, 2007; Janelle, Barba, Frehlich, Tennant, & Cauraugh, 1997; Wulf, 2007). A secondary goal is then to examine the efficacy of script training for AOS. Youmans et al. (2011) provided promising initial evidence supporting its efficacy for AOS, yet no studies have replicated these findings (Ballard et al., 2015). The results of this study suggest that self-controlled feedback is more efficacious in treating adults with AOS than clinician-controlled feedback. Greater improvements of performance for self-controlled feedback were noted especially in accuracy of productions. There was the potential to impact rate of speech as well. Findings across conditions (treated versus untreated scripts) also indicate that script training is an efficacious method of treating adults with AOS. / Public Health
492

A Systematic Examination of Practice Amount in Childhood Apraxia of Speech (CAS) Treatment Using an Integral Stimulation Approach

Welsh, Mackenzie January 2017 (has links)
The purpose of this study was to examine how a critical principle of motor learning, practice amount (high number of trials versus a low number of trials), affects speech motor learning in childhood apraxia of speech (CAS). It also sought to contribute to the literature base regarding using an integral stimulation approach for these children. Currently, a limited evidence base exists for decision-making regarding practice amount in CAS treatment. Using a single-case experimental design with two participants, three target sets of utterances (High Amount, Low Amount, and Control) received different amounts of treatment. Outcomes were compared in terms of retention. Targets were scored regarding perceptual (prosodic and segmental) accuracy. Effect sizes were computed to quantify the extent of treatment effects. For both participants, results show some evidence suggesting a higher amount of practice is advantageous and leads to greater learning. A low amount of treatment did not show clear differences compared to not receiving any treatment. Caution should be taken when interpreting these findings due to its small sample size and modest effects. Results suggest that the integral stimulation approach may only be effective if provided with a significantly high amount of practice. Further research is needed to examine how the principles of motor learning and the integral stimulation approach should be sensibly and systematically applied to promote best outcomes for this population. / Communication Sciences
493

The effects of a perceptual-motor development program on children with Developmental Coordination Disorder

Walters, Yolinda 12 1900 (has links)
Thesis (M Sport Sc (Sport Science))--University of Stellenbosch, 2005. / The purpose of this study was to determine the effectiveness of a perceptual-motor development programme for children with Developmental Coordination Disorder (DCD), as identified on the Movement Assessment Battery for Children (M-ABC). A pre- and post-test design was employed in the study and data were reported as case studies. The programme included a cognitive approach to perceptual-motor activities, with special attention to visual perception. The intervention programme was implemented over six consecutive weeks, with two 45-minute sessions each week. The motor proficiency of nine of the 12 children who participated in this study improved to the point where they were no longer classified as having DCD. The reasons for this improvement could be attributed to the regular practise provided by the perceptual-motor activities that were the content of the program and to the method of presentation, i.e. the cognitive strategies that were child-centred, which could have helped develop self-confidence in the children. These results are in agreement with the research of Schoemaker and Kalverboer (1994) that many children with DCD may learn to overcome or cope with their movement problems. The three children who performed most poorly on the M-ABC pre-test did not improve over the course of the intervention programme. A thorough examination of their perceptual-motor system could provide more information about the various factors that may contribute to their movement problems. It is also possible that the programme simply was not long enough for these children (they did not get enough practise) and/or they were not able to respond to the child-centred cognitive approach in such a short period of time.
494

Facteurs influençant la consolidation et l’apprentissage d’une habileté motrice chez l’humain

Trempe, Maxime 04 1900 (has links)
La pratique physique a longtemps été perçue comme le déterminant premier de l’apprentissage du mouvement. Souvent exprimée par l’expression « Vingt fois sur le métier remettez votre ouvrage», cette idée se base sur l’observation qu’une grande quantité de pratique est nécessaire pour maîtriser un geste technique complexe. Bien que l’importance de la pratique physique pour l’apprentissage du mouvement demeure indéniable, il a récemment été démontré que les changements neurobiologiques qui constituent les bases de la mémoire prennent place après la pratique. Ces changements, regroupés sous le terme « consolidation », sont essentiels à la mise en mémoire des habiletés motrices. L’objectif de cette thèse est de définir les processus de consolidation en identifiant certains facteurs qui influencent la consolidation d’une habileté motrice. À l’aide d’une tâche d’adaptation visuomotrice comportant deux niveaux de difficulté, nous avons démontré qu’une bonne performance doit être atteinte au cours de la séance de pratique pour enclencher certains processus de consolidation. De plus, nos résultats indiquent que l’évaluation subjective que l’apprenant fait de sa propre performance peut moduler la consolidation. Finalement, nous avons démontré que l’apprentissage par observation peut enclencher certains processus de consolidation, indiquant que la consolidation n’est pas exclusive à la pratique physique. Dans l’ensemble, les résultats des études expérimentales présentées dans cette thèse montrent que la consolidation regroupe plusieurs processus distincts jouant chacun un rôle important pour l’apprentissage du mouvement. Les éducateurs physiques, les entraineurs sportifs et les spécialistes de la réadaptation physique devraient donc planifier des entrainements favorisant non seulement l’acquisition de gestes moteurs mais également leur consolidation. / Physical practice has long been regarded as the single most determinant factor of motor skill acquisition. Often expressed by the old adage “practice makes perfect,” this idea easily relates to the common observation that extensive practice is necessary to master complex motor skills. Although the importance of physical practice for motor skill learning is undeniable, recent evidence demonstrates that the neurobiological changes that constitute the foundation of memory occur after physical practice. Regrouped under the term “consolidation”, these changes are essential for the memory storage of motor skills. The objective of this thesis was to identify factors that influence motor skill consolidation. Using a visuomotor adaptation task with two levels of difficulty, we showed that a good performance must be attained during practice to trigger certain consolidation processes. In addition, our results indicate that the learner’s subjective evaluation of his/her own performance can also modulate consolidation. Finally, we showed that observation triggers consolidation processes, indicating that consolidation is not exclusive to physical practice. Together, the results presented in this thesis demonstrate that consolidation regroups several distinct processes that each plays an important role for motor skill learning. Physical education teachers, athletic coaches and rehabilitation specialists should therefore plan training schedules favoring not only motor skill acquisition but also motor skill consolidation.
495

The Effects of Perceptual Motor Enrichment Upon a Six Year Old with Cerebellar Brain Damage

Shepardson, Nina F. (Nina Fredrica) 08 1900 (has links)
This study involved the effects of a perceptual motor enrichment program upon the motor skills of a six year old boy with cerebellar brain damage, who, with a control group of ten normal six year olds, was given a pre-test of motor skills. He and a child from the control group participated in a perceptual-motor enrichment program. The motor skills of both subjects were tested halfway through the program. Following the program, the experimental child, the control child, and the control group were post-tested on their motor skills. The testings showed that the greatest gains in motor skills were obtained by the experimental child, followed by the control child. The control group displayed little increase in motor skill performance.
496

Formy a metody výuky snowboardingu na základních a středních školách na Táborsku / Forms and methods of snowboarding at primary and secondary schools in the region Tabor

Zamrzlová, Alena January 2015 (has links)
This master thesis deals with the issues of snowboard teaching of children at older school age. The master thesis is divided into theoretical and practical part. The theoretical part describes the ride techniques and two fundamental but very different snowboard styles - freestyle and alpine. This part also presents the methodology of teaching and single elements of snowboarding methodical streak, that are acquired by motor learning. The motor abilities, skills and other factors that are related to snowboarding are explained here, too. Because this thesis is aimed at the snowboard teaching at elementary schools, the theoretical part is focused on integration of snowboarding into School Education Programme and on qualifications of teachers. The method of questioning used in the practical part tries to find out, if the snowboarding lessons for children at older school age are part of the school education in the region Tabor and what are the conditions of such an education. This part also deals with its technical and material provision. On winter training courses of one elementary school a research was done using the observational method and experiment. This research is aimed at snowboard teaching of pupils - beginners, who had different type and level of equipment and observes, how quickly are they...
497

Etude des mécanismes comportementaux et neurophysiologiques consécutifs à un entrainement par imagerie motrice / Study of behavioral and neurophysiological mechanisms following motor imagery training

Ruffino, Célia 12 December 2017 (has links)
Dans la littérature, de nombreuses recherches dans le domaine du contrôle moteur, des sciences du sport ou encore de la rééducation se sont intéressées à l’apprentissage moteur consécutif à un entrainement mental. Cependant, plusieurs mécanismes, qu’ils soient comportementaux ou neurophysiologiques, demeurent encore aujourd’hui peu étudiés. Dans notre première étude, nous avons montré qu’il était impossible de prédire la future amélioration de la performance suite à un entrainement mental aigu, sur une tâche de vitesse-précision, par la simple évaluation subjective des capacités d’imagerie chez une population jeune. Il apparait cependant essentiel de produire des images claires et précises tout au long de l’entrainement pour obtenir de meilleures performances in fine. De plus, par l’analyse fine de la performance, nos résultats ont montré, dans notre seconde étude, les véritables effets des répétitions imaginées sur la mémorisation des habiletés motrices. L’entrainement mental est également apparu efficace pour compenser le déficit de mémoire motrice rapidement observable dans la population âgée. Enfin, une troisième étude a révélé que les répétitions d’un mouvement imaginé pouvaient modifier, de façon transitoire, le codage des réseaux neuronaux impliqués dans le processus de mémoire motrice. / For many years, research in motor control, sport science and rehabilitation focused on the performance improvement following mental practice. However, some mechanisms, behavioral and neurophysiological, remain insufficiently understood. In our first study, we demonstrated the impossibility to predict the future performance improvement following imagined repetitions of a speed accuracy trade-off task, with a subjective evaluation of imagery ability of young healthy individuals. However, it is essential to produce clear and vivid mental simulations throughout the training to obtain a better performance improvement. Besides, by a further analysis of performance, the results of our second study have shown the real impact of mental training on the memorization of motor skills. Motor imagery training also appeared to be effective to compensate the motor memory deficit observed in the elderly. Finally, a third study revealed that the repetitions of imagined movements could modify, temporarily, the coding of neural networks involved in the motor memory process.
498

Liberdade na escolha da resposta e momento da estabilização em aprendizagem motora / Freedom in response choice and moment of stabilization in motor learning

Araujo, Ulysses Okada de 13 March 2009 (has links)
O estudo teve como objetivo investigar, a partir de uma perspectiva de processo adaptativo em aprendizagem motora, o efeito da liberdade na escolha da resposta em diferentes momentos do processo de estabilização. A possibilidade de escolher a ordem dos componentes que compõem uma seqüência de movimentos (liberdade na escolha da resposta) tem se mostrado benéfica à aquisição de habilidades motoras. Contudo, o efeito da liberdade na escolha da resposta pode ser mediado pelo processo de estabilização funcional. Para investigar esta hipótese, 135 voluntários com média de idade de 22 (± 4,1) anos, de ambos os sexos, foram alocados a nove grupos experimentais, derivados da combinação de três condições experimentais (SEM, MED e ALT) e dois momentos da estabilização (antes e após a estabilização inicial do desempenho). A liberdade na escolha da resposta foi operacionalizada neste estudo como a possibilidade de escolher a ordem de uma seqüência de toques em sensores, em uma tarefa complexa de timing coincidente. Os resultados mostraram que não houve efeito da condição experimental do início da prática no desempenho na fase de adaptação, porém condições intermediárias de liberdade de escolha no final da prática não apresentaram queda na consistência frente à modificação da tarefa. Nesse sentido, a liberdade na escolha da resposta não trouxe prejuízos à adaptação / The objective of the study was to investigate, from an adaptive process perspective on motor learning, the effect of freedom in response choice in different moments of the stabilization process. The possibility of choosing the order of the components which generate a movement sequence (freedom in response choice) has been shown as beneficial to motor skills acquisition. However, the effect of freedom in response choice could be mediated by the process of functional stabilization. To investigate the hypothesis, a hundred thirty-five volunteers with mean age of 22 (± 4,1) years were assigned to nine experimental groups, derived from the combination of three experimental conditions (SEM, MED and ALT) and two moments of stabilization (before and after initial performance stabilization). Freedom in response choice was manipulated in this study as the possibility of choosing the order of tapping a sequence of sensors, in a complex anticipation timing task. Results showed there was no effect of experimental condition in the beginning of practice in performance in adaptation phase, although intermediate conditions of freddom of choice didnt show decrease in consistency following task modification. In this sense, freedom in response choice wasnt detrimental to adaptation
499

Learning to throw

Frömer, Romy 04 February 2016 (has links)
Feedback, Trainingsplan und individuelle Unterschiede zwischen Lernern sind drei Faktoren die den motorischen Fertigkeitserwerb beeinflussen und wurden in der vorliegenden Dissertation untersucht. Ein besonderer Fokus lag auf den zugrundeliegenden Gehirnprozessen von Feedbackverarbeitung und Handlungsvorbereitung, die mittels ereigniskorrelierter Potenziale (EKPs) untersucht wurden. 120 Teilnehmer trainierten auf virtuelle Zielscheiben zu werfen und wurden in einer Folgesitzung auf Abruf und Transfer getestet. Der Trainingsplan verursachte entweder hohe contextual interference (CI) (randomisiert) oder niedrige CI (geblockt). In einer anschließenden Onlinestudie, bearbeiteten 80% der Teilnehmer eine Untermenge der Raven advanced progressive matrices, die schlussfolgerndes Denken (SD) erfassen. Unter hoher CI hängt besseres SD mit größerem Zuwachs im Training und höherer Performanz in Abruf und Transfer zusammen. Ähnliche Effekte von SD im späten Trainingsverlauf unter niedriger CI lassen darauf schließen, dass Variabilität eine notwendige Voraussetzung für positive Effekte von SD ist. Wir folgern, dass CI das Ausmaß an Praxisvariabilität über den Trainingsverlauf beeinflusst und darüber moduliert, ob Regeln abstrahiert werden (Studie 1). Diese Interpretation wird durch differenzielle Lerneffekte auf EKPs in der Vorbereitungsphase gestützt. Hohe CI führt zu einer stärkeren Abnahme von aufmerksamkeits- und kontrollbezogenen EKPs während der Vorbereitungsphase. Die CNV Amplitude, als Maß motorischer Vorbereitungsaktivität nimmt zu, wenn die Anforderungen in Training und Abruf gleich sind, wie bei niedriger CI. Das spricht für zwei parallele Mechanismen motorischen Lernens, die gemeinsam zur CNV Amplitude beitragen (Studie 2). Wir zeigten außerdem, dass sich graduelle Verarbeitung positiven Performanz-Feedbacks in der Variation der Amplitude der Reward Positivity widerspiegelt (Studie 3). / Feedback, training schedule and individual differences between learners influence the acquisition of motor skills and were investigated in the present thesis. A special focus was on brain processes underlying feedback processing and motor preparation, investigated using event related potentials (ERPs). 120 participants trained to throw at virtual targets and were tested for retention and transfer. Training schedule was manipulated with half of the participants practicing under high contextual interference (CI) (randomized training) and the other half under low CI (blocked training). In a follow-up online study, 80% of the participants completed a subset of the Raven advanced progressive matrices, testing reasoning ability. Under high CI, participants’ reasoning ability was related to higher performance increase during training and higher subsequent performance in retention and transfer. Similar effects in late stages of low CI training indicate, that variability is a necessary prerequisite for beneficial effects of reasoning ability. We conclude, that CI affects the amount of variability of practice across the course of training and the abstraction of rules (Study 1). Differential learning effects on ERPs in the preparatory phase foster this interpretation. High CI shows a larger decline in attention- and control-related ERPs than low CI. CNV amplitude, as a measure of motor preparatory activity, increases with learning only, when attention demands of training and retention are similar, as in low CI training. This points to two parallel mechanisms in motor learning, with a cognitive and a motor processor, mutually contributing to CNV amplitude (Study 2). In the framework of the “reinforcement learning theory of the error related negativity”, we showed, that positive performance feedback is processed gradually and that this processing is reflected in varying amplitudes of reward positivity (Study 3). Together these results provide new insights on motor learning.
500

Learning sensori-motor mappings using little knowledge : application to manipulation robotics / Apprentissage de couplages sensori-moteur en utilisant très peu d'informations : application à la robotique de manipulation

De La Bourdonnaye, François 18 December 2018 (has links)
La thèse consiste en l'apprentissage d'une tâche complexe de robotique de manipulation en utilisant très peu d'aprioris. Plus précisément, la tâche apprise consiste à atteindre un objet avec un robot série. L'objectif est de réaliser cet apprentissage sans paramètres de calibrage des caméras, modèles géométriques directs, descripteurs faits à la main ou des démonstrations d'expert. L'apprentissage par renforcement profond est une classe d'algorithmes particulièrement intéressante dans cette optique. En effet, l'apprentissage par renforcement permet d’apprendre une compétence sensori-motrice en se passant de modèles dynamiques. Par ailleurs, l'apprentissage profond permet de se passer de descripteurs faits à la main pour la représentation d'état. Cependant, spécifier les objectifs sans supervision humaine est un défi important. Certaines solutions consistent à utiliser des signaux de récompense informatifs ou des démonstrations d'experts pour guider le robot vers les solutions. D'autres consistent à décomposer l'apprentissage. Par exemple, l'apprentissage "petit à petit" ou "du simple au compliqué" peut être utilisé. Cependant, cette stratégie nécessite la connaissance de l'objectif en termes d'état. Une autre solution est de décomposer une tâche complexe en plusieurs tâches plus simples. Néanmoins, cela n'implique pas l'absence de supervision pour les sous tâches mentionnées. D'autres approches utilisant plusieurs robots en parallèle peuvent également être utilisés mais nécessite du matériel coûteux. Pour notre approche, nous nous inspirons du comportement des êtres humains. Ces derniers généralement regardent l'objet avant de le manipuler. Ainsi, nous décomposons la tâche d'atteinte en 3 sous tâches. La première tâche consiste à apprendre à fixer un objet avec un système de deux caméras pour le localiser dans l'espace. Cette tâche est apprise avec de l'apprentissage par renforcement profond et un signal de récompense faiblement supervisé. Pour la tâche suivante, deux compétences sont apprises en parallèle : la fixation d'effecteur et une fonction de coordination main-oeil. Comme la précédente tâche, un algorithme d'apprentissage par renforcement profond est utilisé avec un signal de récompense faiblement supervisé. Le but de cette tâche est d'être capable de localiser l'effecteur du robot à partir des coordonnées articulaires. La dernière tâche utilise les compétences apprises lors des deux précédentes étapes pour apprendre au robot à atteindre un objet. Cet apprentissage utilise les mêmes aprioris que pour les tâches précédentes. En plus de la tâche d'atteinte, un predicteur d'atteignabilité d'objet est appris. La principale contribution de ces travaux est l'apprentissage d'une tâche de robotique complexe en n'utilisant que très peu de supervision. / The thesis is focused on learning a complex manipulation robotics task using little knowledge. More precisely, the concerned task consists in reaching an object with a serial arm and the objective is to learn it without camera calibration parameters, forward kinematics, handcrafted features, or expert demonstrations. Deep reinforcement learning algorithms suit well to this objective. Indeed, reinforcement learning allows to learn sensori-motor mappings while dispensing with dynamics. Besides, deep learning allows to dispense with handcrafted features for the state spacerepresentation. However, it is difficult to specify the objectives of the learned task without requiring human supervision. Some solutions imply expert demonstrations or shaping rewards to guiderobots towards its objective. The latter is generally computed using forward kinematics and handcrafted visual modules. Another class of solutions consists in decomposing the complex task. Learning from easy missions can be used, but this requires the knowledge of a goal state. Decomposing the whole complex into simpler sub tasks can also be utilized (hierarchical learning) but does notnecessarily imply a lack of human supervision. Alternate approaches which use several agents in parallel to increase the probability of success can be used but are costly. In our approach,we decompose the whole reaching task into three simpler sub tasks while taking inspiration from the human behavior. Indeed, humans first look at an object before reaching it. The first learned task is an object fixation task which is aimed at localizing the object in the 3D space. This is learned using deep reinforcement learning and a weakly supervised reward function. The second task consists in learning jointly end-effector binocular fixations and a hand-eye coordination function. This is also learned using a similar set-up and is aimed at localizing the end-effector in the 3D space. The third task uses the two prior learned skills to learn to reach an object and uses the same requirements as the two prior tasks: it hardly requires supervision. In addition, without using additional priors, an object reachability predictor is learned in parallel. The main contribution of this thesis is the learning of a complex robotic task with weak supervision.

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